People used to give me so much crap when I was a kid for reading a book while walking - It never caused me a problem, and I can walk while reading still to this day. These people never had to learn how, I think!

As an programmer: That is just plain wrong for like a decade and even before it's only partially true.
Yes on single processor with single physical and logical core doing one task that uses processor ALL THE TIME it will be completed faster if there are no interruptions.
But if that program requires some IO operations or system calls then in that time other program can execute many lines of code while previous program cannot do anything and just waits.
Also nowadays parallelization is the key to better performance. We are near the peak of how fast single core can be in current technology while adding additional cores is comparably piece of cake. You can easily cram 8 cores on a single die but making one core even 2 times faster is close to impossible in long run [Let's assume the base clock is 3GHz since it's possible now with 8 core cpus, making one core come up to 6GHz requires use of liquid nitrogen for cooling and some serious PSU to even power that thing]. Don't even start on GPUs since those have thousand of cores that are really weak individually.

I'm talking about processing new information like you would have to do while walking on a street or driving a car, not something that can be rehearsed. If you're paying attention to reading, then you aren't paying attention to your surroundings. Your brain automatically filters out a lot of what happens around you. Even that girl and Mr. Marathon wouldn't be able to drive and text safely because you can't read/type a text and pay attention to the road at the same time. impossible.

Had you read any of those studies, or Google 'Supertasker' you'd have learned that everything I said was 100% correct. There exist a small number of people WHO CAN multitask effectively.

Your specific example of driving and texting was almost exactly what was tested in this experiment - people were asked to drive while completing math problems and memorizing words. Almost everyone was terrible at it.

It's anywhere from 1% to 3% of the population, depending on which study and what exactly they are measuring. It's rare, but not so rare that lots of people on FJ aren't supertaskers. These are people who can read and walk at the same time. Believe it or not, some of these people actually perform BETTER while multitasking.

Strayer has since found that about 2.5 percent of people he studies have exceptional abilities. They don't get overloaded. In fact, a few actually get better when doing both tasks at once

Laws against texting and driving exist because 99-97% of us can't do it. But the same studies that show we suck at it, also show that 1-3% of us can do it just fine. People are stupid though, and plenty of people who suck at it will insist they are good at it. So we make laws for the majority.

Built off of the previous study, using some of the same people, and scanned their brains while they attempted to multitask. They were able to identify huge differences in how the brains of supertaskers worked compared to regular suckers who sucked at doing two things at once.

So again, there exist people who are great at multitasking. Most of us suck at it. Some people CAN drive effectively AND pay attention/solve math problems/memorize text/read without a decrease in their driving ability.

There are even some half-serious online tests you can take to see if you might be a supertasker.

I'm referring to the vast majority of people. If 97% of people can't do it, then it's safe to say that "people can't do it" because generally they can't. Exceptions exist, but what i'm saying is that a person's brain isn't capable of it and generally speaking that's true. At any rate, my original point stands that people can't just learn to do this. I made that point because the original comment was saying something along the lines of people need to learn how or whatever i don't remember and I don't care. My whole point was that people haven't learned how because it isn't something that people are capable of. A very rare few can, but that isn't indicative of the human race. Otherwise it wouldn't be called racist to call all blacks murdering thieves.

2.5% is not common. It's not even close. If out of every hundred people you meet there is only about 2 or 3 of them that can multitask effectively then they are not common. If we push that number out to cover the world population, you may be lucky to meet one or two of them. Though statistically speaking you probably won't even meet one. 2% of the world split up over the world is quite a lot of ground for these people to be spaced out over.

Hell over just the US that's 9490ish people per city and town. Now again that sounds big but that's condensing about half the US population already into those areas. Now split that up over the world and those numbers just went to nearly nothing.